Yang Qikun, Huang Jinxin, Zhang Li, Kurbonov Nurbek N, Zhou Shengrui
School of Electrical Engineering, Shandong University, Jinan 250061, China.
School of Continuing Education, Shandong University, Jinan 250100, China.
Materials (Basel). 2025 Sep 22;18(18):4425. doi: 10.3390/ma18184425.
Polyimide (PI) is widely used in aerospace, electronic packaging, and other fields due to its excellent dielectric and thermophysical properties. However, the performance of traditional PI materials under extreme conditions has become increasingly inadequate to meet the growing demands. To address this, this study designed a PI/Nano-SiN advanced composite material and, based on molecular dynamics simulations, thoroughly explored the influence of silane coupling agents with different grafting densities on the interfacial microstructure and their correlation with the overall material's physical properties. The results show that when the grafting density is 10%, the interfacial bonding of the PI/Nano-SiN composite is optimized: non-bonded interaction energy increases by 18.4%, the number of hydrogen bonds increases by 32.5%, and the free volume fraction decreases to 18.13%. These changes significantly enhance the overall performance of the material, manifested by an increase of about 30 K in the glass transition temperature and a 49.5% improvement in thermal conductivity compared to pure PI. Furthermore, the system maintains high Young's modulus and shear modulus in the temperature range of 300-700 K. The study reveals that silane coupling agents can effectively enhance the composite material's overall performance by optimizing the interfacial structure and controlling the free volume, providing an efficient computational method for the design and performance prediction of advanced high-performance PI composites.
聚酰亚胺（PI）因其优异的介电和热物理性能而广泛应用于航空航天、电子封装等领域。然而，传统PI材料在极端条件下的性能已越来越不足以满足不断增长的需求。为解决这一问题，本研究设计了一种PI/纳米氮化硅先进复合材料，并基于分子动力学模拟，深入探究了不同接枝密度的硅烷偶联剂对界面微观结构的影响及其与材料整体物理性能的相关性。结果表明，当接枝密度为10%时，PI/纳米氮化硅复合材料的界面结合得到优化：非键相互作用能增加18.4%，氢键数量增加32.5%，自由体积分数降至18.13%。这些变化显著提高了材料的整体性能，表现为玻璃化转变温度升高约30 K，热导率相比纯PI提高49.5%。此外，该体系在300 - 700 K温度范围内保持较高的杨氏模量和剪切模量。研究表明，硅烷偶联剂可通过优化界面结构和控制自由体积有效提高复合材料的整体性能，为先进高性能PI复合材料的设计和性能预测提供了一种有效的计算方法。
